Place a piece of nori (they should be cut into 8x4 inch / 20x10 centimeter sheets) on the plastic-wrap-covered bamboo mat. The nori should be positioned with the long side toward you and within 1/2 inch (1 centimeter) of the edge of the mat.
Measure out 1/2 cup of the prepared sushi rice and use your hands to spread it as evenly as possible onto the nori. Dip your fingers in the bowl of vinegar if the rice sticks to your hands too much. Sprinkle sesame seeds evenly across the rice. Gently press down on the rice to ensure it will stick to itself and to the nori.
Carefully flip the sheet of nori so that the rice is now on the bottom. The rice should more or less stay attached to the nori and in an even layer.
Place 1-2 pieces of cucumber and 2-4 pieces of tofu on the edge of the nori closest to you. The quantity will depend on preference and the physical capacity of the roll. You can always remove pieces if you’ve overfilled it, but try to get a feel for how much this size piece of nori can contain. Spread about 1 Tablespoon of the lemon cashew butter across the cucumber and tofu.
Lift the edge of the bamboo mat closest to you and carefully pull it over the sushi ingredients. You should hold onto the plastic wrap so that it stays taut against the mat. Apply pressure to the roll so that it rolls as tightly as possible, with no empty space. Also, be careful not to press too hard because doing so will smash the rice and displace the cashew butter. Roll gradually, pulling back periodically, until the roll is relatively round. See the video link in the blog post for a better idea of the process.
Wrap the plastic wrap around the roll and set it aside for now. Prepare the other rolls in the same way.